The atomic number increases moving left to right across a period and subsequently so does the effective nuclear charge. Therefore, moving left to right across a period the nucleus has a greater pull on the outer electrons and the atomic radii decreases.
Answer: The state of maater for HgBr is solid.
Explanation:
A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
A double displacement reaction in which one of the product is formed as a solid is called as precipitation reaction.
The balanced chemical equation is:

Answer: I believe that it's electrons please let me know if it was right or what it was!
Hope this helps!!! Good luck!!! ;)
Answer:
The solution is given below.
Explanation:
Speed = Distance(m)/Time(sec.)
Distance traveled = 150 m
Time taken = 3.5 seconds
Speed of car = 150/3.5 = 42.86 m/s
So the car traveled at a speed of 42.86 m/s.